Discussion
Lead poisoning is one of the medical diagnoses usually forgotten, especially when there is no history of exposure. Many cases with lead poisoning were studied for other causes of abdominal pain and anemia with unknown causes. These patients underwent many unnecessary medical procedures such as endoscopy, colonoscopy, and bone marrow aspiration, in which lead poisoning can be confirmed with a high blood lead level. In the presented family, due to recurrent abdominal colic and other symptoms, they had been worked up for many causes of such symptoms. They attributed their signs and symptoms to mild coronavirus (COVID- 19) infection considering the recent worldwide pandemic. During a few months, they visited many specialists due to chronic pain and muscle weakness. This situation postponed the correct diagnosis. Ultimately, the oldest child who bought the swamp stone powder suspected that they were using this powder by mistake in their food and explained the scenario to their physician. Their BLL was tested, and the results confirmed the diagnosis of lead poisoning. They were referred to our lead poisoning clinic for further evaluation and treatment.
In the presented cases, five people with the same exposure experienced different signs and symptoms. Their BLL was different. They even have different outcomes after receiving the treatment. The parents’ response to treatment was significant comparing to children. All five cases remained symptomatic with toxic BLL and underwent a second course of therapy with an oral chelating agent (Succimer or di-mercaptosuccinic acid). Case 2 also received a third course of therapy with D-penicillamine till she became symptoms-free. The adult cases (parents) had higher BLL than children, but they showed better response to first chelating therapy to see a 32.5 and 26.2% reduction in BLL for parents. As table one shows, the mean reduction in BLL in children under 18 was 1.6%. The youngest patient with age 8 (case 5) had significant resistance to therapy and underwent a third course of oral chelating therapy.
One theory is that because of higher bone density in children; they absorb more lead than adults. After chelation therapy, children have a higher lead body burden and excessive lead release in the bloodstream. This can explain the children’s higher lead level, compared to the parents, after chelation therapy. The younger daughter and son were experiencing attention deficit and difficulty in concentration. One of the reasons for this finding could be that these children were students, and their families and teachers monitored their function at school. So any changes in their cognitive and intellectual function would be noticed.
These findings showed that every patient with vague complaints and suspicious exposure needs to be evaluated for lead poisoning. As clinicians, we should consider heavy metal poisoning as a proper differential diagnosis. Case 2 (mother) used more swamp stone powder and had more symptoms than the other cases. She remained symptomatic after the first session of therapy ( 2 gram intravenous CaNa2 EDTA for five days). She received two following oral Succimer (dimercaptosuccinic acid) courses for 19 days and D-penicillamine 250mg QID for ten days.
After five-month exposure to swamp powder, all cases had a toxic BLL, and they became symptomatic. The high level of lead oxide in this product makes it a potential source for severe lead poisoning. It is important to find the source of the lead poisoning and report it to the responsible organization. Acknowledging the responsible organization can prevent many people from having exposure to lead sources. Physicians should keep in mind the source of the new or unusual ways of lead poisoning like traditional medicine. Many people believe that all herbal or traditional medicine is safe for them and may overuse it. Physicians should ask their patients about traditional medicine when making a diagnosis of lead poisoning with unknown origin. They should warn their patients about the use of dangerous traditional medicine like Swamp powder.